1. Field of the Invention
The present invention is directed to nut-like food compositions which retain a firm texture in high moisture environments, and to processes for preparing said compositions, particularly those compositions which retain their crunchy, nut-like chewing characteristics when employed in high-moisture baked goods.
2. Description of the Prior Art
The prior art contains several references to a class of food products comprising a dispersion of water-immiscible oil droplets in a continuous phase of hydrated hydrophilic film-forming polymer dried to form a cellular structure which simulates the texture of a natural nutmeat. For example, U.S. Pat. No. 2,952,544 describes products of this type which are produced by first admixing the oil component and the dry powdered film-forming component to form a slurry. Moisture is then added with vigorous beating until the particles of film-forming component hydrate and coalesce into a continuous phase which isolates and entraps the uniformly distributed globules of the oil component in a cellular structure. Dispersing the oil component throughout the continuous phase of hydrated film-former results in a gell-like mass which is then slowly dried without disturbing the cellular structure to gradually harden the continuous phase without displacing any of the oil.
The products have the characteristic crisp and oily character of natural nutmeats and, if the ingredients and procedures are selectively employed, may result in a product capable of replacing nutmeats, and even particular varieties of nutmeats. As used herein, the term "simulated nutmeats" is intended to designate the food products briefly described above and disclosed in detail in the aforementioned U.S. Pat. No. 2,952,544, which is incorporated herein by reference.
U.S. Pat. Nos. 3,872,229 and 3,872,230, also herein incorporated by reference, are directed to processes and products wherein greatly improved textural characteristics and eating qualities are achieved in the above-mentioned simulated nutmeat products by forming and mixing the gell-like dispersion of oil component in hydrated film-forming component under conditions which exclude gas; for example, by forming and mixing the dispersion under a vacuum. Although these improved products are quite satisfactory as nutmeat replacements for eating "out of hand", their desirable, firm textural characteristics have proven difficult to retain when the products are exposed to high moisture environments for substantial periods of time; for example, as is required when the simulated nutmeat is included in another food product having a relatively high moisture content.
Coating the individual pieces with an edible moisture resistant coating; for example, by the procedures set forth in U.S. Pat. No. 3,798,338, as mentioned in the above-cited patents, has achieved some success in preventing the simulated nutmeat pieces from becoming soggy or soft in moist food products, especially those products stored at low temperatures such as ice cream. However, this technique is largely dependent on obtaining a substantially pin-hole free coating and has limited application in food products where the pieces are not only subjected to high moistures but also to high temperatures; for example, as is typical of use in most baked products.
Many hydrophilic film-formers, particularly various protein materials, are known to be irreversibly coagulated or denatured by the application of heat or other kinds of energy. In this coagulated state, the previously water-soluble film-forming compound becomes substantially and permanently less water soluble through a type of cross-linking or polymerization reaction. The use of such heat-coagulable film-formers is known in the encapsulation art as a means for providing water-insoluble shells around individual droplets of water-immiscible, and frequently volatile liquids. For examples of such prior art uses of heat coagulable film-formers, see U.S. Pat. Nos. 2,969,330; 3,137,631; and 3,406,119. Film-formers inherently having heat-coagulating properties, particularly albuminoid proteins, have also been previously employed in the formation of the subject simulated nutmeat products because their superior film-forming properties are particularly advantageous in the formation of the continuous phase of the products. However, the utilization of these heat-coagulation properties to provide a substantially more moisture resistant product has heretofore been unknown and unappreciated.